For example, for practice such as operation, medical treatment, and examination in medical institutions such as a hospital, a medical observation device has been proposed, which is configured to enhance a treatment efficiency by observation of an affected area of a patient. Such a medical observation device is attached to, e.g., a tip end portion of a robot arm, and is used such that the arm is operated to set the medical observation device to a necessary direction or angle. This allows observation of the affected area of the patient from a desired direction. Alternatively, the medical observation device is used with a practitioner gripping the medical observation device. An image or a video acquired by the medical observation device is displayed on a display section such as a monitor or a display.
This medical observation device includes, for example, a medical observation device including an imaging optical system configured to acquire an image of an object and an imaging element configured to photoelectrically convert the image of the object acquired by the imaging optical system. Such a medical observation device is configured such that the imaging optical system is disposed in a housing, the imaging element is held by an element holder, and the housing and the element holder are linked together (see, e.g., Patent Documents 1 and 2).